POLYESTER FILM AND GAS-BARRIER POLYESTER FILM

• Main Authors: TANAKA, HIROYUKI, MATSUI, RYOSUKE, HASHIMOTO, KOUKICHI
• Format: Patent
• Language: English; French; German
• Published: 22.12.2004
• Edition: 7
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; COMPOSITIONS OF MACROMOLECULAR COMPOUNDS; GENERAL PROCESSES OF COMPOUNDING; LAYERED PRODUCTS; LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT ORNON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; PERFORMING OPERATIONS; THEIR PREPARATION OR CHEMICAL WORKING-UP; TRANSPORTING; WORKING-UP

In order to provide a polyester film having superior impact resistance and flex pinhole resistance, and further exhibiting superior gas barrier properties after a metal or metal oxide is deposited on the film, with the inherent characteristics of polyester film maintained, such as low hygroscopicity, dimensional stability, flatness, and transparency, the polyester film comprises a mixture of 70% to 97% by weight of polyester A mainly composed of a repeating unit comprising ethylene terephthalate and 3% to 30% by weight of polyester B mainly composed of a repeating unit comprising butylene terephthalate. The polyester film has a melting point in range of 245 to 270 DEG C. The polyester film may comprise a polyester resin containing 90% to 60% by weight of an ethylene terephthalate component, 10% to 40% by weight of a butylene terephthalate component, and 0.1% to 5% by weight of a polyoxyalkylene glycol component. The polyester film is suitably used for packaging and other applications.